On the PWM control of a fishing-line artificial muscle (Twisted and Coiled Polymer Fiber) actuator using a heater and a cooling fan

Abstract

Fishing-line artificial muscle, namely twisted and coiled polymer fiber (TCPF), is one of the soft actuators attracting a lot of attention in recent years. A TCPF actuator is actuated by heat, and is easily made from a commercially available polymer fiber. It is a low-cost, light-weight, large-force, large-stroke, and quiet actuator, however, its efficiency and its response speed are low. This paper focuses on improving the low response speed. We develop a new cooling system with a cooling fan as well as a heating system by a Nichrome wire. A microcomputer (Arduino) controls the system using PWM signal. The proposed system is demonstrated in experiments.